This invention relates to a magnetic scale for use for position detection.
A position detection apparatus for detecting the position of a print head of a printer is known and disclosed, for example, in Japanese Patent Laid-open No. Sho 62-226007 (hereinafter referred to as Patent Document 1).
The position detection apparatus disclosed in Patent Document 1 includes a magnetic scale which in turn includes a guide shaft for guiding a print head. The guide shaft has magnetic graduations provided on an outer peripheral face along a longitudinal direction thereof. The position detection apparatus further includes a magnetic sensor provided integrally on the print head for detecting a variation of the magnetic field of the magnetic graduations and outputting a detection signal.
In the position detection apparatus, the position of the print head in the longitudinal direction of the guide shaft is obtained based on the detection signal.
Such a position detection apparatus which uses a magnetic scale as described above is applied widely to various machine tools, printers and automatic machines in which position detection is required.